When Data Query does not exist, editing throws warnings and not an GUI error

[TheWitness]

Describe the bug

Based upon the user report here:

https://forums.cacti.net/viewtopic.php?t=62809

Users attempting to edit a non-existant Data Query get warning messages in the Cacti log and are not told what to do to resolve the problem.

Expected behavior

Provide a user an error in the GUI and instructions as to what they should do next.

[TheWitness]

Iv'e fixed this in the 1.2.x branch. Did you run the repair_database.php script?